C语言数据类型——整理

C定义的5种整型数据类型

测试代码
程序说明：sizeof是字节操作符，使用方式，sizeof（数据类型）。sizeof的作用是得到数据类型所占的字节数。

#include<stdio.h>int main(void) {printf("sizeof(signed char) = %d/n", sizeof(signed char));printf("sizeof(short int) = %d/n", sizeof(short int)); /* sizeof的结果都是int型 */printf("sizeof(int) = %d/n", sizeof(int));printf("sizeof(long int) = %d/n", sizeof(long int));printf("sizeof(long long int) = %d/n", sizeof(long long int));return 0;}

64位编译环境运行结果

sizeof(signed char) = 1/nsizeof(short int) = 2/nsizeof(int) = 4/nsizeof(long int) = 8/nsizeof(long long int) = 8/n

无符号整型

#include<stdio.h>int main(void) {printf("sizeof(unsigned char) = %d/n", sizeof(unsigned char));printf("sizeof(unsigned short int) = %d/n", sizeof(unsigned short int)); /* sizeof的结果都是int型 */printf("sizeof(unsigned int) = %d/n", sizeof(unsigned int));printf("sizeof(unsigned long int) = %d/n", sizeof(unsigned long int));printf("sizeof(unsigned long long int) = %d/n", sizeof(unsigned long long int));return 0；}

浮点型数据类型

C标准中对不同类型的浮点数有不同的规定，编译器不同或硬件条件不同，字节长度也不相同。

测试代码

#include<stdio.h>int main(void) {printf("sizeof(float) = %d/n", sizeof(float));printf("sizeof(double) = %d/n", sizeof(double));printf("sizeof(long double) = %d/n", sizeof(long double));return 0;}

引用

http://www.360doc.com/content/13/0925/09/9133899_316913649.shtml